CVE-2005-3018 in Safari
Summary
by MITRE
Apple Safari allows remote attackers to cause a denial of service (application crash) via a crafted data:// URL.
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Analysis
by VulDB Data Team • 02/10/2025
The vulnerability identified as CVE-2005-3018 represents a significant denial of service flaw within Apple Safari web browser that was exploited through maliciously crafted data:// URLs. This vulnerability falls under the category of improper input validation and demonstrates how seemingly benign URL schemes can be weaponized to disrupt browser operations. The issue specifically affects Safari versions prior to 2.0.3 and highlights the critical importance of proper URL parsing and validation mechanisms within web browsers.
The technical flaw manifests when Safari encounters a specially crafted data:// URL that contains malformed or excessive data parameters. These URLs are designed to embed data directly within the URL structure itself, typically used for legitimate purposes such as embedding images or small documents. However, the vulnerability occurs when the browser fails to properly sanitize or limit the size and structure of data contained within these URLs, leading to memory exhaustion or stack overflow conditions that cause the application to crash. This type of vulnerability is classified as a buffer overflow or resource exhaustion issue under CWE-122 and CWE-400 categories.
The operational impact of this vulnerability extends beyond simple browser disruption, as it provides remote attackers with a means to systematically degrade user experience and potentially disrupt business operations. When exploited, the vulnerability allows attackers to cause application crashes without requiring any special privileges or user interaction beyond visiting a malicious webpage. This makes it particularly dangerous in environments where users may encounter untrusted content or where automated attacks could be deployed at scale. The vulnerability aligns with ATT&CK technique T1499.004 for network denial of service attacks and represents a classic example of how protocol-level flaws can be leveraged for system disruption.
Mitigation strategies for this vulnerability include immediate patching of affected Safari versions to 2.0.3 or later, which incorporated proper URL validation and data size limiting mechanisms. Browser administrators should also implement network-level filtering to block suspicious data:// URLs and consider deploying web application firewalls that can detect and prevent such malformed URL patterns. Additionally, user education regarding the dangers of visiting untrusted websites and the importance of keeping software updated remains crucial. Organizations should also consider implementing browser hardening measures that restrict the execution of potentially dangerous URL schemes and monitor for unusual patterns of browser crashes that may indicate exploitation attempts. The vulnerability serves as a reminder of the critical need for robust input validation and proper resource management in web browser implementations, particularly when handling embedded data within URL structures.